Expensive Gemstone

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Karat sebagai pengukur belian adalah massa satuan yang setara dengan 0,2 gram (200 mg). Berlian dan batu permata lainnya diukur berdasar berat bukan volume.

The carat (ct) is a unit of mass equal to 200 mg (0.2 g; 0.007055 oz) and is used for measuring gemstones and pearls.

The General Conference on Weights and Measures (French: Conférence générale des poids et mesures - CGPM) is the senior of the three Inter-governmental organizations established in 1875 under the terms of the Metre Convention (French: Convention du Mètre) to represent the interests of member states.

Gemstone Carat Weight Estimation Calculator

1. Jadeite – more than $3 million per carat

This gemstone is actually a pyroxene mineral, usually of apple green, emerald green, bluish green or leek green in color. There have also been some that are either greenish white or white with some green spots. Jadeites are colorless in the thin section of the stone. The more intense the green, the more expensive the stone will get. The Chinese, however, also value the white jadeite with green spots. A deep blue-green jadeite that emits a translucent hue has also been discovered in recent times in Guatemala. While it is considered valuable because of historical reasons as the Mesoamerican Olmec used it, the rarity of this specific kind of jadeite has yet to be established. Once the Guatemalans start actively mining for it and confirms its rarity, the value may increase even more.

2. RedDiamonds – $2 million to 2.5 million per carat

This gemstone is very rare. Most of it are actually purplish red, and not crimson or pure red. A mining company located in Australia gets to find only a small number of red diamonds every year. These are then sold at an auction once every couple of years, and you can just imagine the interest, demand and price that the red diamonds command.

3. Serendibite – $1.8 million to 2 million per carat

The serendibite gemstone is an extremely rare mineral that bears boron. Only two areas have been known to produce quality serendibite, namely Ratanapura in Sri Lanka and Mogok in northern Burma. Most of the serendibites found are blue green, grayish blue or pale yellow with a white streak.

4. Blue Garnet – $1.5 million per carat

There are many kinds of garnet in the market. You can find it in a variety of colors, from black, brown, green, orange, pink, purple, red and yellow. There have even been some that do not have any color. But none can compare to the price of the blue garnet. This gemstone was discovered in Madagascar in the 1990s, though it has since been mined in Russia, the United States and Turkey as well. While it has a blue green shade, the generous amount of vanadium in the stone makes it emit a purplish hue when it is held against incandescent lighting.

5.Grandidierite – $100,000 per carat

Alfred Grandidier was a natural historian famed in the archaeology world for his discovery in Madagascar of the skeletons and remains of an elephant bird that weighed half a ton and that has been extinct for thousands of years.  He is also famous in the world of gemology for discovering in Sri Lanka a rare stone that transmits blue, green and white light. Initially, they thought it was the gemstone serendibite, but after closer scrutiny, gemologists concluded that it was a totally new stone. It was thereafter named after Grandidier.

6. Painite – $50,000 – 60,000 per carat

Discovered in the 1950s by the Englishman Arthur C. Pain, painite is a rare borate material. It has a natural hexagon shape and has an orange-red or brownish-red color. Trace amounts of iron, vanadium and chromium are present in the stone.  While it used to be the rarest stone in the world, more have been unearthed and discovered in Burma recently.

7. Musgravite – $35,000 per carat

This gemstone is actually a silicate mineral that was first discovered in Australia in an area called Musgrave. While similar minerals have since been unearthed in Madagascar, Greenland and Sri Lanka, it is still considered very rare. There are trace amounts of aluminum, berrylium and magnesium present in the stone.

8. Bixbite – $10,000 per carat

This gemstone is also known as the red beryl emerald. It is very rare and has been found only in a couple of places in Utah called Juab County and Beaver County, and in Sierra County in New Mexico. Most of the red beryl that are gem-grade can be found in Violet Claim. This is located in the Wah Wah Mountains of midwest Utah. A Filmore, Utah local named Lamar Hodges discovered the bixbites by accident. He was a mineral prospector who was actually looking for uranium when he stumbled upon the red beryls.

9. Black Opal – $2,355 per carat

Opal is the national gemstone of Australia, which produces 97 percent of the world’s supply. The southern portion of the country alone produces 80 percent of all opals. Opal is not a mineral, as it is actually an amorphous form of silica that is related to quartz. Up to 20 percent of the stone’s weight is made up of water.  The internal structure of this gemstone makes it diffract light, and it may come in a variety of colors ranging from blue, brown, gray, green, magenta, olive, orange, pink, red, rose, slate, white and yellow. But the most rare and most expensive are the black opals. The stone has also been unearthed in Brazil, Mexico, the United States, Mali and Ethiopia.

10. Jeremejevite – $2000 per carat

This gemstone is actually made of aluminum borate mineral with fluoride and hydroxide ions. Pavel Vladimirovich Eremeev discovered it in Siberia. Most of this stone are colored blue or yellow. White and colorless versions of this gem have also been discovered. Jeremejevite has since been unearthed in other areas as well, notably in Namibia, the Eifel District in Germany and the Pamir Mountain area in Tajikistan.

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